F Khan1,2, A Mat3, A E Hogan3, B D Kent1, S Eigenheer1, M A Corrigan3, D O'Shea3,4, M W Butler1,2. 1. From the Respiratory Department, Clinical Research Centre, St Vincent's University Hospital, Dublin, Ireland. 2. Respiratory Department, University College Dublin, Dublin, Ireland. 3. Endocrine Department, Clinical Research Centre, St Vincent's University Hospital, Dublin, Ireland. 4. Endocrine Department, University College Dublin, Dublin, Ireland.